Circuit continuity and illumination intensity control system for groups of electric lamps



May 2, 1933. R B, HUNTER 1,906,860

CIRCUIT GONTINUITY AND ILLUMINATION INTENSITY CONTROL SYSTEM FOR GROUPS OF ELECTRIC LAMPS Filed Dec. 12, 1950 2 Sheets-Sheet 1 @M/MWM 3 mm 8a. "@NW 8 JMXW May 2, 1933. R. B. HUNTER CIRCUIT CONTINUITY AND ILLUMINATION INTENSITY CONTROL SYSTEM FOR GROUPS OF ELECTRIC LAMPS Filed Dec. 12, 1950 2 Sheets-Sheet 2 4 L l L @Hl E3 a 8 6 5 47? 14 10 c f 25 d oand enactment at 'nation intensity effects so preselected.

Patented May 2, 1933 Laos-360 UNITED STATES PATENT OFFICE RICHARD B. HUNTFfR, OF, SHOREWOOD, WISCONSIN, ASSIGNOR TO CUTLER-Hm,

INC., 013 MILWAUKEE, WISCONSIN,

A CORPORATION OF DELAWARE CIRCUIT CON TINUITY AND ILLUMINATION INTENSITY CONTROL SYSTEM FOR GROUPS OF ELECTRIC LAMPS Application filed December 12, 1930. Serial No. 501,892.

This invention relates to improvements in circuit continuity and illumination 1ntensity control systems for groups of electric lamps, and the invention more particularly relates to multiple-scene preset illumination intensity control systems of the aforementioned character.

An object of the invention is to provide novel means enabling preselection of a plurality of different illumination intensity effects for a lamp or lamps in a given circuit, together with means for effecting enactment of such effects at will in predetermined sequence.

Another object is to provide control means of thecharacter last mentioned for each of a number of groups of lamps, together with means for jointly controlling enactment of the illumination intensity effects preselected for certain or all of such groups of lamps.

Another object is to provide means, of the aforementioned character whereby the changes from the obtaining intensities of illumination ofthe groups of lamps to the intensities of illumination respectively preselected therefor are effected gradually.

Another object is to provide novel means whereby certain or all of the respective groups of lamps may be subjected in common to control by any one of a number of illumination intensity regulating elements.

-Another object is to provide circuit continuity controlelements which are properly 'co-ord inated with the several illumination intensity regulating elements.

Another and more specific object is to provide means enabling preselection of a number of illumination intensity effects to be afforded by the groups of lamps jointly,

will of the joint illumi- Another object is 'to provide a multiplescene illumination intensity and circuit continuity control system which is extremely flezfible'in character and exceedingly simple in operation. Other objects and advantages of the invention will hereinafter appear.

The accompanying drawings illustrate .an embodiment of the invention which will now be described, it being understood that the embodiment illustrated is susceptible of modification within the scope of the appended claims.

In the drawings, Figures 1 and 2, considered together, illustrate schematically and diagrammatically an illumination control system constructed in accordance with my invention.

Certainv features of the control system herein disclosed are described and claimed in my copending application filed October 11, 1930, Serial No. 488,185.

Referring to the drawings, the numerals 10, 11, 12 and 13 designate groups of electric lamps such as are commonly used in theaters, auditoriums and the like. While I have shown only three lamps in each group, it is to be understood that a larger number of lamps will ordinarily be included in each group. Also it is to be understood that the lamps in each particular group will ordinarily be of like color, but in order to obtain the desired lighting effects it is preferred to employ lamps in certain J groups which differ in color from the lamps of other groups. For instance, it may be assumed that the lamps in group 10 repre sent the white foot-lights, and those in group 11 the white border lights, of a stage; whereas the lamps in group 12 may represent the red foot-lights, and those in group 13 the red border lights, of such stage. As will be understood, the number ofgroups of lamps and the colors of the lamps employed may be varied as desired to meet the requirements of each particular installation.

Included in circuit with each group of,

lamps is a suitable current controlling or regulating device, such as the dimmer rheostats designatedrespectively by. the numerals 14, 15, 16 and 17. As will be apparent to those skilled in the art similar or equivalent regulating devices may be substituted for the dimmer rheostats illustrated,-as, for instance, electron tubes with grid control, or magnetic amplifier type dimmers in which the current in the direct current coils is varied.

Continuity of circuit of the respective groups of lamps is controlled by the normally open contacts of electromagnetically operable switches 18,19, 20 and 21, the energizing circuits of the operating windings of said switches being subject to control individually by the selector switches 22, 23, 24 and 25, respectively, or jointly in a group or in groups by relaying control from said selector switches to any one or certain of the single-pole master control switches 26, 27 28 and 29. Thus upon closure of selector switches 22 to 25 through the stationary contacts 0. thereof, respectively, the operating windings of switches 18 to 21 are connected directly across lines L, L". Each of the switches 22 to 25 may likewise be closed through the stationary contacts I), 0, (l and e thereof to relay control of the energizing circuits of the operating windings of switches 18 to 21, inclusive, to any one or more of the master control switches 26 to 29, respectively. For instance, by closing all of the selector switches 22 to 25 at the stationary contacts 1) thereof, the circuits of all of the groups of lamps will be completed upon closure of master control switch 26; or if certain or all of the switches 22 to 25, in-

clusive, are closed at the stationary contacts 0 thereof the circuits of the corresponding groups of lamps 10 to 13, inclusive, will be completed upon closure of master switch 27. Movement of selector switches 22 to 25, inclusive, to position (1 relays control of circuit continuity to master switch 28; and movement of said selector switches to position e relays control of circuit continuity to master switch 29. Any desire grouping of the lamp circuits for circuit continuity control thereof may thus be effected.

Assuming energization and closure of all of the switches 18 to 21, inclusive, the circuits of all of the groups of lamps 10 to 13, inclusive, will be completed,-the 'iniitial intensity of illumination of the lamps in each group being dependent upon the respective positions of the. contact arms 14 to 17, inclusive, of the dimmer rheostats. Each of said cont-act arms is shown in an intermediate or mid-position, which may be assumed to provide for half-bright illumination intensity of therespective groups of lamps,-it being understood that when said arms are in their lower extremefpositions full-bright illumination intensity of the respective groups will be provided,-whereas when said contact arms are in their upper extreme positions full-dark or zero illumination intensity of the respective groups will be provided without requiring positive or actual interruption of the lamp circuits.

Means are associated with said groups of lamps to provide for movement or adjustment of each of the aforementioned rheostat contact arms 14 to '17, respectively, automatically from any given position thereof to any one of a number of other preselected positions,the positions to be assumed by each rheostat contact arm being presclectable individually, and initiation or enactment of the change or changes required in the positioning of the respective contact arms being subject to control individually and independently of each other. or the changes required for an desired number of the lamp circuits may e initiated jointly by means of a common control instrumentality. Means are also provided whereby certain or all of the groups of lamps may be subjected in common to control by any one of a number of illumination intensity regulating elements.

The aforementioned automatically operaable control means for each dimmer rheostat 1 1, 15, etc., comprises essentially a plurality of sending rheostats 1, 2 and 3, each connected across lines L L and corresponding in number to the number of scenes for which it is desired to preset the illumination intensities of the respective groups of lamps. Each of said means also comprises a receiving rheostat 4 which is likewise connected across lines L If. The rheostats 1, 2 and 3 are provided with manuall adjustable arms 1, 2" and 3, respective y, and each rheostat 4 is provided with a power-operated arm 4. Each of the arms 4 is electrically connected by means of a conductor 5 with one end of the coil 6 of a polarized relay of well known form,- the other end of said coil being connected (Figs. 1 and by means of a conductor 7 with the contactor 8 of a selector switch 9. Arms 1", 2 and 3 of rheostats 1, 2 and 3 are alternatively connectable selectively through contacts 1", 2, 3 and conductors 1, 2, 3 with the stationary contacts a of the respective selector switches 9.

As shown the contacts 1, 2 and 3 are carried by and form parts of the multi-pole scene switches 30, 31 and 32, respectively. Thus upon u ward movement of scene switch '30. to e ect closure of all of the contacts 1", the sending rheostats 1 will rendered effective for controlling or regutor switches. Similarly upon closure of contacts 2 by upward movement of scene switch 31 the sending rheostats 2 will be rendered effective, and upon closure of contacts 3 by upward movement of scene switch 32 the sending rheostats 3 will be rendered effective. Switches 30, 31 and 32 may of course be arranged for operation at will in any desired sequence, but I prefer to employ means for effecting closure thereof in a predetermined sequence. Said means as shown may comprise a.shaft 33 having cams 30, 31 and 32 fixed thereto and adapted to effect closure and opening of the contacts of switches 30, 31 and 32 in predetermined sequence upon movement of handle member 34 of shaft 33 to different angular positions.

Thus assumin for example, that the contactors of selector switches 22 to 25, inclusive, have been moved into engagement with the stationary contacts 6 thereof; and further assuming that the arms 1 of the several sending rheostats .1 have been moved to their lower extreme positions to preselect full bright intensity of each of the groups of lamps 10 to 13, inclusive. Then upon closure of master switch 26 and simultaneous closure of the multiple contacts of switch 30 (by operation of handle 34), each of the lamp circuits will be completed at initial half-bright intensity of illumination of the lamps, and intensityrof illumination of all groups will be gradually and automatically changed to full-bri ht.

The means for automatically effecting the gradual change from the obtaining intensity of illumination of each group of lamps to the intensity of illumination preselected therefor are described in detail in my copending application aforementioned; but I will herem explain the operation of such means for one of the groups of lamps, say group 10, it being understood that the control means will be substantially duplicated for each of the other groups of lamps.

' Thus with contacts 1 of switch 30 closed and with the contactor 8 of selector switch 9 in engagement with the stationary contact a; with the arm 4 of receiving rheostat 4 in mid-position. as illustrated and with the arm 1 of sending rheostat 1 in its lower extreme position, as aforementioned, it will be noted that the sending rheostat 1, ing rheostat 4 and coil6 of the polarized relay are arranged in the form of a Wheatstone bridge.

With the bridge circuit unbalanced by the aforedescribed relatively different positions of the rheostat arms 1 and 4 current will flow through the coil 6 in a direction to cause movement of the relay contactor 6 to the left into engagement with its stationary contact 6*. This will complete an energizing circuit for a solenoid coil 34,

energy supply,

receiv-s of the bridge circuit. Arm 14 which circuit mav be traced from line L by 'a motor 43 common to the pinions 42 associated with the groups of lamps 10 and 11, suitable speed reducing gearing 43 being preferably interposed in the drive. Motor 43 is also preferably provided with a rheoeta-i143 of wellknown form to enable variation of the speed of said motor. Motor 43 may be connected with any suitable source of The upper end of member 41 is attached to but insulated from the arm 4 of receiving rheostat 4 and the arm 14 of the intensity varying rheostat 14. Accordingly due to the lower extreme positioning of the arm 1 of sending rheostat 1, the arm 4 of rheostat 4 will be gradually moved as, for instance, lines L L downwardly to its lower extreme position,

thus balancing the bridge circuit with resultant neutral or intermediate positioning of relay contactor 6. As will be understood arm 14 is constrained to move down wardly at a rate and to a degree corresponding with the movement of arm 4, so that the aforedescrihed operation of balancing the bridge rircuit will result in extreme lower positioning of arm 14 to provide full-bright intensity of illumination of the lamps in group 10.

Ifit be assumed that the arm 2 of sending rheostat 2 has been preset in its upper extreme position to preselect full-dark 01' zero intensity of illumination of the group of lamps 10, then upon opening of the contacts 1 of scene switch 30and substantially simultaneous closure of contacts 2 of scene switch 31, the Wheatstone bridge circuit will obviously be unbalanced in the opposite sense to cause engagement of relay contactor 6 with contact 6. Accordingly the solenoid coil'44 will be energized through a circuit extending from line L by conductor 35 to relay contactor 6 and contact 6, (onductor 45 through coil 44, and by conductors 46 and 40 to line L Rack 41 of double rack member 41 is thus drawn to the left into engagement with pinion 42, and arm 4 of receiving rheostat 4 is driven to its upper extreme position to effect re-balancing of dimmer rheostat 14 is of course simultaneously gizing circuits of said relay driven to its upper extreme position to fully dim the lamps in group 10.

From the foregoing it will be apparent that innumerable combinations of lighting effects may be obtained by means which is simple and definite in operation. Any number of the groups of lamps may be rendered inactive during enactment of a given scene, or at any time by proper manipulation of the individual circuit continuity control switches 22 to 25 and/or the master control switches 26 to 29.

Suitable means are'employed to indicate at all times the instantaneous position of each of the arms 14*, 15*, etc., of the dimmer rheostats; said means preferably comprising an indicating voltmeter 47 associated with each of the receiving rheostats 4 in the manner illustrated, said voltmeters being preferably calibrated to indicate directly the degree of illumination intensity provided by the instantaneous positions of the respective dimmer rheostats 14, 15, etc.

I have provided means operable independently of the respective Wheatstone bridge circuits to effect movement of each of the.

dimmer rheostats arms 14, 15*, etc., to its upper extreme position whereby full-dark or zero intensity of illumination of the respective groups of lamps is provided. Said means as shown comprises relays 37 each havin its normally closed contacts 37 included in circuits with one of the solenoid coils 34. i

The windings energized simultaneously by closure of a single push button switch 48, the energizing circuits of said relay windings being obvious.

Thus upon opening of the respective relay contacts 37 the solenoid coils 35 are rendered ineffective to provide for any farther downward movement of the rheostat arms 14, 15, etc., irrespective of an unbalanced condition of the respective bridge circuits such as to cause engagement of the polarized relay contactors 6* with the relay contacts 6.

In addition to and cooperable with the means last described for preventing any increasein the intensity of illumination of the respective groups of lamps, I have also provided a plurality of relays 49 the normally open contacts 49" of which when closed respectively provide energizing circuits for the several solenoid coils 44 to simultaneously initiate. and effect upward movement of the rheostat arms 14, 15, etc., for dimmingof the respective groups of lamps. As shown the windings o relays 49 are preferably arranged for energization simultaneously by closure of a single push button 50, the enerwindings being obvious. As will be apparent to those skilled in the art, if all ofthe bridge circuits .are balanced at the time whenpush button switch '50 is closed (as when the intensity of illumiof relays 37 are preferably nation preselected for each of the groups of lamps has been attained) the contactors 6 of the several polarized relays will be in intermediate or neutral position, and hence depression of push button 48 will not be necessary.

Assuming adjustment of the rheostats 14 to 17, inclusive, either individually or jointly, to provide different intensities of illumination of the respective groups of lamps 10 to 13, in certain instances it is desirable to provide means for dimming certain or all of the groups of lamps in such a manner that dimming of the group or groups of lamps having the greatest intensity of illumination will first be initiated and thereafter dimming of the group or groups of lamps having a lesser intensity of illumination will be initiated, so that all of the active groups will be finally brought to zero intensity of illumination at the same instant.

For example, let it be assumed that in attaining a given combination of illumination intensities of the respective groups of lamps the arm 14 of rheostat 14 is located in its lower extreme position to provide full-bright intensity of illumination of the group of lamps 10, that arms 15 and 16 of rheostats 15 and 16 are in the mid-positions thereof, as illustrated, to provide for half-bright intensity of illumination of groups 11 and 12, and that arm 17 a of rheostat 17 is in its upper extreme position to provide for zero intensity of illumination of group 13. Let it be further assumed that the arm 8 of each selector switch 9 has been moved into engagement with its cooperating contact 0, and that the arm 52 of the master rheostat 52 has been moved to its lower extreme position, so that it would normally preselect full-bright intensity of illumination of the respective groups of lamps controlled thereby. -However, in this particular operation of the system push button switch 48 will be depressed to energize the relays 37 and thus open the contacts 37 thereof for disabling the res ective solenoids 34. In this manner each 0 the rheostat arms 14 to 17 inclusive, will be prevented from moving toward the fullbright position thereof.

On the other hand, upon upward movement of manually operable switch 56 to effect closure of its contacts 52 each of the polarized relay coils will be included in a 17 to increase the intensities of illuminabridge circuits for the scribed, however, tlfe respective solenoids 34 are disabled due to opening of the contacts 37 of relays 37. Moreover, by gradually movin upwardly the arm 52 of rheostat 52 the Vheatstone bridge circuit controlling the group of lamps 10 is unbalanced in a manner to cause gradual dimming of said group of lamps. Moreover, when arm 52 reaches the mid-point of rheostat 52 the bridge circuits controlling the groups of lamps 11 and 12 will be balanced, and continued upward movement of arm 52 will cause unbalancing of said bridge circuits to likewise effect gradual upward movement of rheostat contactor arms 15 and 16 Assuming continued movement of arm 52 to its upper extreme position, the rheostat contactor arms 14", 15 and 16 will thereafter be moved gradually and simultaneously to their respective upper extreme positions to fully dim the lamps in the groups 10, 11 and 12. Inasmuch as the rheostat contactor arm 17=was assumed to be initially positioned for full dimming of the group of lamps 13, it will be understood that the aforedescribed upward movement of arm 52 would have no effect whatsoever upon the rheostat 17. Various other methods of manipulatin the parts of my control system will rea ily suggest themselves to those skilled in the art.

The elements aforedescribed provide for attainment of certain novel and valuable results, including more particularly the means enabling multiple scene set-ups of the illumination intensities to be provided by the respective groups of lamps. I will now describe certain additional control eleinents which may be readily combined with those aforementioned to render the. illumination intensity and circuit continuity control system still more flexible in character. Thus I provide for each group of lamps an additional sending rheostat 51 which may be substituted for any one or all of the sending rheostats 1, 2 and 3 as a part of the Wheatstone bridge circuit by merel moving the arm 8 of t e selector switch 9 from engagement with contact a into engagement with contact I). By this means I provide for attainment of any desired any way distur change in the intensity of illumination of the respective roups of lamps without in ing the set-ups provided by presetting of'the sending rheostats 1, 2' and 3 controlled jointly by the scene switches 30, 31 and 32. Moreover, it will be apparent that the rheostats 51 may be utilized to provide jointly for an additional illumination intensity effect by the several groups of lamps. In such case certain or all of the sending rheostats 51 would be pre-adjusted and the change in the illumination intensity effect initiated byquickly moving certain or all of thearms 8 of selector switches :9 from their a positions to their 6 positions.

The advantages of such an arrangement will be apparent to those skilled in the art. I have also provided means whereby a common sending rheostat may be employed for any two or more of the Wheatstone bridge circuits; and whereby said bridge circuits may be co-ordinated for joint control in groups irrespective of the lamp colors. Said means as shown may comprises. plurality of sending rheostats 52, 53, 54 and 55, the arms 52", 53*, 54 and 55 of which may be pre-adjusted as desired. Thus assuming a predeterminedadjustment of the arm 52 ofsending rheostat 52, the coils 6 of any'or all of the polarized relays may be preset for energization control thereby by merely moving the contactors 8 of the respective selector switches 9 into engagement with the contacts 0 thereof. Thereafter the bridge circuits of each of which the rheostat 52 is to form a part may be rendered active by operation of the multipole switch 56 to effect simultaneous closure of its contacts 52.

In like manner the coils 6 of any or all of the polarized relays may be preset for energization .control by rheostat 53' by moving the contactors 8 of selector switches 9 into engagement with the contacts d; multi-pole switch 57 being adapted upon closure of its contacts 53 to effect joint enactment for the respective groups of lamps of the illumination intensity effect preselected by the ad justment of rheostat 53. Similarly rheostat 54 may be rendered effective for jointly controlling the illumination intensity effect of any or all of the groups of lamps by move ment of the contactors 8 into engagement with the respective contacts 6 and thereafter operating switch 58 to contacts 54".

Rlieostat 55 may be rendered effective'for jointly controlling the illumination intensity effect of any or all of the groups of lamps by movement of the contactors 8 into en- V gagement with the respective contacts f and thereafter operating switch 59 to effect closure of its contacts 55. Obviously if desired any group of the contactors 8 of selector switches 9 may be engaged with one of their contacts a, d, a or f and other of said contactors 8 may be engaged with another of their respective contacts, such mixed group control being initiated by simultaneous operation of the corresponding switches 56, 57 58 or 59. I

Various other possible operations of my illumination intensity control scheme. will be apparent to those skilled in the art. Thus where it is desired to subject certain or all of the groups of lamps to a series of joint illumination intensity control effects, the sending rheostats 52 to 55 may be indiing means comprising a devices,

' combination, a lam vidually adjusted as desired, the selector switch contactors 8 and the multi-pole switches 56 to 59, inclusive, being thereafter operated in the required manner to efiect group control of the illumination intensity effect of the several groups of lamps in the desired sequence.

It is, to be understood that the movable contactors 8 of selector switches 9 and the contactors of selector switches 22 to 25, inelusive, are each preferably movable to an ofl' position between any two on positions thereof, res ectively.

What I c aim as new and desire to secure by Letters Patent is:

1.'-In an illumination control system, in combination, a lamp circuit, intensity control means therefor and current regulating means for said lamp circuit to be preset for action subject to control by said intensity control means, said current regulating means com rising a plurality of sending devices, a ollow-up receiving device common to said sending devices, said intensity control means being operable to selectively render eflI'ective any .one of said sending and means to effect a current change in said lamp circuit varyin with the follow-up movement required 0 said receiving device.

2. In an, illumination control system, in

circuit, intensity control means there or comprising switch mechanism including a selector switch and multiple-preset current regulating means for said lamp circuit to be controlled by said switch mechanism, said current regulatlurality of adjustable sending devices, a ollow-up receivin device common to said sending devices, sai switch mechanism being operable to selectively render effective any one of said send ing devices, and means controlled by said sending devices respectively to effect current chan es in said lamp circuit varying with the ollow-up movements required of said receiving device.

3. In an illumination control system, in combination, a plurality of. lamp circuits, individual intensity control means therefor including a corresponding number of selector switches, multiple individual current regmating means for each of said lamp circuits t e parts of which are adapted to be reset for delayed action alternatively subject to control by said selector switchesrespectively, each of said current regulating means including power operated means whereby the dela ed current change-of each lamp circuit is e ected gradually, and'means associated with t e respective selector switches to afford o tional joint control of the regulating means for a plurality of said lamp circuits.

4. In an illumination control system, in

'ing devices of said groups combination, a plurality of lamp circuits, intensity control means therefor comprising an individual selector switch associated with each lamp circuit and multi-pole scene switches associated with said selector switches jointly, multiple individual current regulating means for each of said lamp circuits the parts of which are adapted to be preset for delayed action alternatively subject to control by said scene switches respectively, each of said current regulating means including means whereby the delayed current change of each lamp circuit is effected gradually, and means associated with the respective selector switches to afford optional joint control of the regulating means for a plurality of said lamp circuits, said last mentioned means including means for rendering a single current regulating element common to the current regulating means for two or more of said lamp circuits.

5. In an illumination control system, in combination, a; plurality of lamp circuits, intensity control means therefor comprising an individual selector switch associated with each lamp circuit and multi-pole scene switches associated with said selector switches jointly, multiple individual current regulating means for each of said lamp circuits the parts of which are adapted to be preset for delayed action alternatively subject to control by said scene switches respectively, each of said current regulating means comprising a plurality of'sending devices, a follow-up receiving device and means to effect gradual current chan es in the lamp circuits varying with the ollow-up movements required of the respective receiving devices, means including said multi-pole scene switches to afford optional joint control of the regulating means for a plurality of said lamp circuits, and means also associated with said selector switches for renderin a single current regulating element effective for varyin the value of current in two or more of said lamp circuits.

6. In an illumination control system, in combination, a plurality of lamp circuits, individual current regulating means therefor operable independently of one another, each of said regulating means comprising a multiplicity of sending devices, a follow-up receiving device and means to effect gradual current changes in the lamp circuits varying with the follow-up movements required of the respective receiving devices, means subject to manual control for rendering certain or all of the corresponding sendingdevices of the respective groups effective r causing said gradual current changes for a given 1 scene, said la st-mentioned means being thereafter operable at will to render other sendetfective in sequence to provide the desired current values in the several lamp circuits fora multiplicity of scenes, and associated means affording individual and/or joint circuit continuity control of said lamp circuits under the conditions aforementioned.

7. In an illumination control system, in combination, a plurality of lamp circuits, individual current regulating means therefor operable independently of one another, each of said regulating means including individually operable automatic means to eifect gradual change or changes of the current in the respectivelamp circuit and furdently of each justable at will to predetermine difi'erentther including multiple means to be preset for action selectively to vary the gradual change or changes to be eifected, and each means affording controlof said lamp circuits individually or in a group or groups for continuity of circuit and for delayed action of their respective regulating means.

8. In an illumination control system,'in combination, a plurality of lamp circuits, individual current regulating means therefor operable independently of one another, each of said regulating means including individ ually operable automatic means to effect gradual change or changes of the current in the respective. lamp circuit and each further including multiple means to be preset for action selectively to vary the'gradual change or changes to be effected, separate controllers associated with each of said lamp circuits to afl'ord circuit continuity control therefor and delayed action of the respective regulating means, and multiple master controllers associated with the aforementioned controllers and operable selectively to afford in respect of a plurality of said circuits continuity control and delayedaction of their regulating means.

9. In an illumination control system, in combination, a lamp circuit and a poweroperated current regulatortherefor, having means for predetermining in advance a plurality of current changes without initiation thereof'and for automatically rendering such changes gradual, said regulator also having multiple control elements operable indepenother at will to selectively effect response without regard to the degree of such changes respectively. 10. In an illumination control system, in combination, a group or bank of electric lamps and circuit controlling means therefor, illumination intensity regulating means included in circuit with said group of lamps, and means for efi'ecting adjustment of said regulating 11 calls, saidlast mentioned means comprising a plur lity'of sending elements, a receiving elemen I to be connected with said sending elements selectively in the form of a Wheatstone bridge, said sending elements being re-adof said regulator for any' of the changes predetermined by said means,

nda polarized relay,

degrees of unbalancing of said bridge, means i for rendering said sending elements active selectively, means associated with said relay coil for effecting movement of said receiving element to gradually re-ba-lance said bridge, and, means for causing said regulating means to simulate the action of said receiving'element in each instance, whereby said sending elements may be utilized to preselect a multiplicity of dilferent intensities of illumination of said lamps.

11. In an illumination control system, in combination, a group or bank of electric lamps and circuit controlling means therefor, illumination intensity regulating means included in circuit with said group of lamps, and means for eifecting adjustment of said regulating means, said last mentioned means comprising a plurality of sending elements, a receiving element and a polarized relay to be connected with said sending elements selcctively in the form of a Wheatstone bridge, said sending elements being pie-adjustable at will to predetermine different degrees of unbalancing of said bridge, means for rendering said sending elements active selec' tively, means associated with said relay coil for effecting movement of said receiving element to gradually re-balance said bridge, means for causing said regulating means to simulate the action of said receiving element tion of said lamps, and electrical means operable independently of said sending elements and said relay for minimizing the illumination intensity effect of said group of lamps while maintaining the circuit connections of the latter.

12. In an illumination control system, in combination,a plurality of groups of electric lamps, each group of lamps having means individual thereto for preselecting and regulating the illumination intensities thereof, said individual means comprising a plurality of sending elements, a receiving element and a polarized relay to be connected with said sending elements selectively to form a Wheatstone bridge, and a plurality of 'multi-pole scene switches operable sethe correspondlcctively to render effective ing sending elements of each of said groups for simultaneously varying the illumination intensities of the respective groups of lamps. 13. In an illumination control system, in combination, a plurality of groups of electric lamps, each means individual thereto for preselecting and regulating. the illumination intensities thereof, said individual means comprising a plurality of sending elements, a receiving element and a polarized relayto be connectgroup of lamps having edwith said sendingelements selectively to c form a Wheatst'one bridge, a plurality of multi-pole scene switches operable selectively to render effective the corresponding sending elements of eachof said groups for simultaneously varying the illumination intensities of the respective groups of lamps, a plurality of additional sending elements, and alternative master control means for rendering any or all of said intensity regulating means subject to control by any or all of said additional sending elements selectively.

14. In an illumination control system, in combination, a plurality of groups of electric lamps, each group of lamps having means individual thereto for controlling continuity of the circuit thereof and multiple means individual thereto for regulating the intensities of illumination thereof, means for relaying circuit continuity control from each of said individual means to any one of a number of master control instrumentalities, each of said intensity regulating means comprising multiple means operable at will to preselect a plurality of different intensities of illumination of the lamps controlled thereby, and power means operable automatically under control of said last-mentioned means for gradually changing from the obtainin intensity of illumination of each group 0 lampsto one of the. ifntensities of illumination preselected there- 15. In an illumination control system, in combination, a plurality of groups of electric lamps, each group of lamps having means individual thereto for controlling continuity of the circuit thereof and means individual thereto for regulating the intensities of illumination thereof, means for relaying circuit continuity control from each of said individual means to any one of a number of master control instrumentalities, each of said intensity regulating means comprising multiple means operable at will to preselect a plurality of different intensities of illumination of the lamps controlled thereby, means operable automatically for gradually changing from the obtaining intensity of? illumination of each group of lamps to one'of the intensities of illumination preselected therefor, and means for varying relatively .to each other the rates of change of certain of the groups of lamps from the obtaining intensities of illumination to the intensities of illumination preselected therefor.

16. In an illumination control system, in combination, a plurality of groups of electric lamps, each group of lamps having means individual thereto for regulating'the intensities of illumination thereof, each of said intensity regulating means comprising multiple means operable at will to preselect a plurality of different intensities of illumination of the lamps controlled thereby,

means operable automatically for simultaneously effecting gradual changes from the obtaining intensities of illumination of the several groups of lamps to certain of the intensities of illumination respectively preselected therefor, and means for varying relatively to each other the rates of certain of such changes in the intensities of illumination of the respective groups of lamps.

17. In an illumination control system, in combination, a plurality of groups of lam )9, means individual to each group of lamps for preselecting a given intensity of illumination thereof, means operable automatically for effecting a gradual change from the obtaining intensities of illumination of the respective groups of lamps to the intensities preselected therefor, electroresponsive means subject to manual control for rendering said automatic means ineffective to increase the intensities of' illumination of: the respective groups of lamps, and means comprising a manually operable common control instrumentality for gradually dimming all of said groups of lamps, the arrangement being such that the dimming effect on the respective groups of lamps is initiated in a sequence depending upon the relative intensities of illumination thereof initially.

18. In an illumination control system, in combination, a plurality oflam'p circuits, individual intensity control means therefor, multiple individual current regulating means for each of said lamp circuits the parts of which are adapted to be preset for delayed action alternatively subject to control by said intensity control means respectively, each of said current regulating means including means whereby the delayed current change of each lamp circuit is effected gradually, means associated with the respective intensity control means to afford optional joint control of the current regulating means for a plurality of said lamp circuits, said last mentioned means including a manually operable control instrumentality common to said groups of lamps, and associated means' for disabling said common control. instrumentalityas to certain normal control functions of the latter.

19. In an illumination control system, in combination, a plurality of? groups of electric lamps, each group of lamps having means individual thereto for preselecting and regulating the illumination. intensities thereof, said individual means comprising a plurality of sending elements, a receiving element and a polarized relay to be connected with said sending elements selectively to form a VVheatstone bridge, a plurality of multi-pole scene switches operable selectively to render effective the corresponding sending elements of each of said groups for s1- multaneously varying the illumination intensities of the respective groups of lamps,

neoaseo a plurality of additional sending elements, alternative master control means for rendering anyv or all of said intensity regulating means subject to control by any one or more of said additional sending elements selectively and associated means operable at will for partially disabling the respective polarized relays during control thereof by one or more of said additional sending elements to. thereby prevent certain normal changes in the intensities of illumination of the re spective groups pf lamps.

20. In' an illumination control system, in combination, a plurality of groups of lamps, means individual to each group of lamps for preselecting a given intensity of illumination thereof, means operable automatically for effecting a gradual change from the obtaining intensities of illumination of the respective groups of lamps to the intensities preselected therefor, electroresponsive means subject to manual control for rendering said automatic means ineffective to increase the intensities of illumination of the respective groups of lamps while maintaining the energizing circuits of the latter, and associated means comprising a manually operable common control instrumentality for gradually dimming all of said groups of lamps under the conditions last mentioned.

21. In an illumination control system, in combination, a plurality of lamp circuits, intensity control means therefor comprising a single selector switch associated with each lamp circuit and multi-pole scene switches associated with said selector switches joint- 1y, multiple individual current regulating means for each of said lamp circuits the parts of which are adapted to be preset for delayed action selectively subject to control by said scene switches respectively, and additional switching means associated with the respective selector switches to afford optio'nal jointcontrol of the regulating means for a plurality of said lamp circuits, saidlast mentioned means including meaus for rendering a single current regulating element common to the current regulating means for two or more of said lamp circuits.

22. In an illumination control system, in combination, a plurality of lamps circuits,

intensitycontrol meanstherefor comprising a single selector switch associated with each lamp circuit and multi-pole scene switches associated with said selector; switches jointly, multiple individual current regulating means for each of said lamp circuits the parts of whichare adapted to be preset for delayed action sele tively subject to control by said scene swit es respectively, means including said multi-pole scene switches to afford optional joint control of the regulating means for a plurality of said lamps circuits, and additional switching means associated with said selector switches for rendering a single current regulating element solely effective for varying the value of current in two or more of said lamp circuits.

23. In an illumination control system, in combination, a plurality of groups of electric lamps, each group of lamps having means individual there to for controlling continuity of the circuit thereof and means individual thereto for regulating the' intensities of illumination thereof, means for relaying circuit continuity control from each ties of illumination to the intensities of illumination preselected therefor.

24. In an illumination control system, in combination, a plurality of groups of electric lamps, each group of lamps having 'means individual thereto for-regulating the intensities of illumination thereof, each of said intensity regulating means comprising multiple means operable at will to preselect a multiplicity of different intensities of illumination of the lamps controlled thereby, power operated means subject to manual control for simultaneously changing from the obtaining intensities of illumination of the several groups of lamps to any of the intensities of illumination respectively preselected therefor, and means for var ing relatively to each other the rates 0 certain of such changes in the intensities. of illumination of the respective groups of lamps.

25. In an illumination control system, in combination, a plurality of groups of electric lamps, each group of lamps having means individual thereto for preselecting and regulating the illumination intensities thereof, said individual means comprising a plurality of sending elements, a receiving element and a polarized relay to be connected with said sending elements selectively to form a Wheatstone bridge, and manual means operable at will to render effective the correspondin sending-elements of each of said groups or simultaneously .varyingthe illumination intensities of the respective groups of lamps.

electric lamps, each group of lamps having means individual thereto for preselecting and atin the illumination intensities thereo said individual means comprising a plurality of sending elements, a receiving element and a polanzed relay to be connected with said sending elements selectively to form a Wheatstone bridge, and manual means operable at will to render effective the corresponding sending elements of each of said groups for simultaneousl varying the illumination intensities of t e respective grou s bf lamps, said manual means also inclu in means for certain 0 said sending selectively rendering elements individu y effective for simultaneously varying the illumination intensities of two or more of said groups of lamps.

In witness whereof, I have hereunto subscribed my name. f

RICHARD B. HUNTER. 

